[HN Gopher] Agrivoltaics: A Sustainable Synergy Between Agricult...
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       Agrivoltaics: A Sustainable Synergy Between Agriculture and Solar
       Energy
        
       Author : thunderbong
       Score  : 88 points
       Date   : 2023-05-13 13:59 UTC (9 hours ago)
        
 (HTM) web link (mercurialtrends.com)
 (TXT) w3m dump (mercurialtrends.com)
        
       | sholladay wrote:
       | The writing style of this article is very repetitive and drawn
       | out. Maybe AI generated?
       | 
       | > Reduced Greenhouse Gas Emissions
       | 
       | > Agrivoltaic systems can also help to reduce greenhouse gas
       | emissions in agriculture. Traditional farming methods rely
       | heavily on fossil fuels for irrigation, transportation, and
       | fertilizer production. These activities contribute significantly
       | to greenhouse gas emissions, which contribute to climate change.
       | 
       | > They can also help to reduce greenhouse gas emissions by
       | generating clean energy from solar panels. By using renewable
       | energy, farmers can reduce their reliance on fossil fuels, which
       | can help to lower their carbon footprint. Additionally,
       | Agrivoltaic systems can reduce the need for conventional
       | electricity, which is often generated from fossil fuels."
        
         | seu wrote:
         | Human or AI generated, it's clearly SEO optimized. I think
         | that's the real problem.
        
           | samwillis wrote:
           | Really I blame Google for this, obviously any online
           | publication needs to optimise for traffic, they need to pay
           | the bills. But Google's latest algorithm changes quite
           | clearly prioritise longer prose, and so bulking out text in
           | articles has become the norm. It's a shame, and Google have
           | the resources to do better, but unfortunately not the
           | incentives. Most of the pages have some amount of Google ads
           | on them.
        
             | friendswdorthy wrote:
             | Edit: oh okay just downvote because of an observation. Nice
             | community here!
        
       | vrglvrglvrgl wrote:
       | [dead]
        
       | [deleted]
        
         | jackmott wrote:
         | [dead]
        
       | hosh wrote:
       | This is a specific application of a broader design pattern found
       | in the permaculture world: planting combinations of plants at
       | different canopy layers, ecological functions, and yields. The
       | solar panels would be taking the place of an understory or shrub
       | canopy layer, while there are herbaceous, ground cover, and root
       | zone layers you can work with.
       | 
       | While solar panels have an yield useful for humans, it would be
       | even better if it can participate in the ecological system.
       | Planting instead say, a palo verde would yield edible beans, with
       | the tree itself acting as a nitrogen fixer. A sea buckthorne tree
       | also acts as a nitrogen fixer, with roots propogating (more sea
       | buckthrone trees pops up on its own) and yields high vitamin-c
       | berries.
       | 
       | What ecological function can a solar panel contribute to?
        
         | Rhapso wrote:
         | How do solar panels interact with condensation?
        
           | hosh wrote:
           | I don't know. But that gets into the broader design pattern
           | of engineering a microclimate, whether that is changing local
           | humidity and temperature levels.
           | 
           | Perhaps, the structure itself can also provide some other
           | functions. The pylons, for example, can double as a way for
           | deep root watering.
        
         | mrDmrTmrJ wrote:
         | Providing shade and lowering peak temperatures - allowing
         | sensitive plants to survive in a broader range of climate &
         | light conditions.
        
           | hosh wrote:
           | That's a result of occupying a certain canopy layer. Any
           | other plant that occupies that canopy layer can do the same.
        
       | Gasp0de wrote:
       | I would assume that the biggest factor in this would be that the
       | racks and solar panels make it very difficult to use large
       | machinery such as tractors and harvesting machines? Somehow this
       | isn't even addressed.
        
         | epistasis wrote:
         | Seems pretty straightforward to seeing appropriate machinery
         | and use that instead of machinery designed for an entirely
         | different setting.
        
         | 867-5309 wrote:
         | these look geared towards small-scale, high $/kg farming for
         | berries, veg, and other hand-picked food. I'd imagine anything
         | on a larger scale for high-yield grain farming would be a waste
         | of land
        
         | toomuchtodo wrote:
         | The racking is either spaced to allow machinery between rows,
         | or panels are suspended using cables and a structure above the
         | machinery max height. Not a consideration for crops that are
         | hand harvested.
         | 
         | https://www.farmersjournal.ie/agrivoltaics-can-crops-and-sol...
         | 
         | https://d3mdtxxgfz6upn.cloudfront.net/WEBFILES/000/753/181/1...
        
         | __MatrixMan__ wrote:
         | If you're already putting structures in the field with the
         | plant, I wonder if they could support the movement of smaller
         | machines that do the same task.
         | 
         | Instead of driving a factory over the crop, imagine a variety
         | of smaller robots zooming around on rails or something. Like
         | https://farm.bot but huge.
        
         | samwillis wrote:
         | Farm machinery got "big" because it enables one human to be
         | more productive, cover more area in one unit of time. Human
         | time is one of the most expensive resources in farming.
         | 
         | As we automate more farming, and move to self operated
         | machinery, we can shrink those machines down again. We can
         | design fleets of machines to work in tandem, and operate around
         | other structures, such as solar. The age of the tram lines is
         | going to come to an end.
         | 
         | This also provides opportunities for replacing chemicals with
         | small robots, such as for weeding.
        
           | Throw73849 wrote:
           | Or maybe use illegal cheap labour from another country.
           | Something like feudalism, but more modern!
        
             | samwillis wrote:
             | You joke, but there are a lot of crops that can't easily be
             | machine picked, and probably never will be. Although I'm a
             | proponent for legal safe immigration for sessional work
             | with a route to permanent residency. The lack of legal
             | routes results in unsafe working conditions and modern
             | slavery.
        
               | ianai wrote:
               | Ah but now supplemented with a push to legalize child
               | labor in the US.
        
               | samwillis wrote:
               | Child labour is already legal (to some extent) in
               | agriculture, unfortunately.
        
               | ianai wrote:
               | And even more often overlooked by those benefiting from
               | it.
        
               | Throw73849 wrote:
               | Why would I joke? People are cheaper than machines.
               | 
               | Edit: "illegal" in terms of work law, minimal salary and
               | safety standards. Legally imported workers are probably
               | even cheaper and easier to exploit!
               | 
               | Until we establish socialism, human labour will always be
               | exploited and cheaper than machines!
        
               | samwillis wrote:
               | My mistake, I usually assume someone openly proposing
               | illegal immigration, rather than safe legal immigration,
               | as a solution is joking.
        
           | shalmanese wrote:
           | > Human time is one of the most expensive resources in
           | farming.
           | 
           | Not any more. A combine costs around a million bucks and has
           | a total useful lifespan of about 10,000 hours which is $100
           | an hour (not counting maintenance and fuel costs which approx
           | doubles this rate) which far exceeds the cost of a human
           | operator. Capital costs exceed labor costs for almost all
           | types of farming these days.
        
         | sholladay wrote:
         | I would also like to see that discussed. There may be enough
         | space on the ground for more compact machinery to do a similar
         | job. Each machine might be less productive, but they would cost
         | less, so you could have more of them and the operation would be
         | more parallelized.
        
         | MadcapJake wrote:
         | You're correct that this is limited to manual harvesting but
         | isn't that pretty common for partial shade crops?
        
           | baron816 wrote:
           | Partial shade crops include broccoli, asparagus, kale,
           | carrots, brussels sprouts, peas...basically all the healthy
           | stuff. Adding a whole second revenue stream to their
           | production would make them more competitive with the
           | unhealthy stuff (corn, rice, wheat).
        
             | ianai wrote:
             | Corn is an absolute miracle. It probably took hundreds of
             | years for native Americans to cultivate and domesticate
             | corn to the nutrient crop we know. Those three crops feed
             | humanity. They shouldn't be shunned for what modern food
             | processing practices. The US alone produces enough corn to
             | feed well over 2 billion people per year.
        
               | baron816 wrote:
               | Sure, but it's just imbalanced in people's diets,
               | partially because of the cost differential.
        
           | Valgrim wrote:
           | It's also pretty common to use solar fields for pasturing,
           | especially where the slopes are too steep for heavy
           | machinery.
        
       | newsclues wrote:
       | Do we have electric tractors?
       | 
       | Are they viable given that weight is a serious issue for
       | machinery on fields?
       | 
       | Having lived on a rural farm, with solar panels on the barn, if
       | you can use the harvested power on the farm, great, but once you
       | start trying to distribute it, the problems start to show up
       | because rural infrastructure isn't good, and there isn't enough
       | demand in the local grid.
        
         | toomuchtodo wrote:
         | Sounds feasible. You'd need battery storage or less batteries
         | and orchestration to charge farm equipment during solar
         | production hours if no grid connection available, but micro
         | grids are a well worn path at this point. Very popular in
         | Australia's western geography and their Northern Territory,
         | where there is not much transmission infra to speak of.
         | 
         | https://electrek.co/2022/11/23/caterpillar-demonstrates-firs...
        
         | worldsayshi wrote:
         | > infrastructure isn't good
         | 
         | I've heard this enough times that I might assume this is the
         | bottle neck of a green transition of our electrical generation.
         | What is being done about this? Is it an area where innovation
         | or disruption can still happen? Are there any interesting
         | things on the horizon for taking big leaps on fixing the
         | electricity infrastructure? As a Fullstack/Cloud/Data engineer
         | where could you put your feet down to contribute to solving
         | this problem?
        
       | jmartrican wrote:
       | Having solar panels might be a good way to hedge your bets
       | against a bad harvest. I imagine it can get quite sunny during a
       | drought.
        
       | seydor wrote:
       | PVs are always raised off the ground.
       | 
       | This is not some new invention, people just planted some stuff
       | under the PVs.
       | 
       | You can also get some goats to clean the weeds in the place
       | before that. They will appreciate the shaded area (but hopefully
       | not the cables)
        
         | pfdietz wrote:
         | > PVs are always raised off the ground.
         | 
         | Not true.
         | 
         | https://www.erthos.com/
        
       | weinzierl wrote:
       | One of the incentives the article doesn't mention is property
       | tax. Where I live, agricultural land is taxed much less than
       | other property. The moment you put solar on your meadow you pay
       | the regular rate. I think it would be fair if property kept its
       | agricultural tax status if it is used in an environmentally
       | friendly way.
        
         | konschubert wrote:
         | But in turn, this means that solar plants will be developed to
         | have pretend-farming below it.
        
           | weinzierl wrote:
           | Not at all. My opinion is that you should be taxed the same
           | way no matter how you use the energy that falls on your soil
           | from the sky. It shouldn't matter if it goes through
           | chlorophyll or silicon.
        
             | konschubert wrote:
             | So you're saying that solar farm land should be taxed like
             | farmland?
             | 
             | That would remove the bad incentives. Personally I agree.
        
       | mirpetri wrote:
       | Plants love sun, why would I put them below a panel into shade.
       | 
       | Article mentions blueberries which I grow and those which get the
       | sunshine only half of the day (partly in shade) don't have the
       | same sweet taste as other in better sunny spots of my garden.
        
         | olddustytrail wrote:
         | > Plants love sun
         | 
         | No. Some plants love direct sunshine and others don't.
        
           | cellularmitosis wrote:
           | Unfortunately the article just hand-waves on this point,
           | leaving it at "certain crops":
           | 
           | > However, certain crops are better suited for this system
           | due to their ability to thrive under partial shade.
        
         | voisin wrote:
         | You can get bifacial panels that let light filter through. Not
         | sure what is filtered, but perhaps the remainder is sufficient
         | for certain crops?
        
           | Mistletoe wrote:
           | Here is a chart of DLI (daily light integral) needed for lots
           | of common crops.
           | 
           | https://www.horti-growlight.com/en-gb/typical-ppfd-dli-
           | value...
           | 
           | Here is a map of DLI in the USA by month.
           | 
           | https://www.researchgate.net/figure/Maps-of-monthly-
           | outdoor-...
           | 
           | So there is some wiggle room maybe. Looks like about 30 is
           | good DLI and the USA gets 40-60 in the summer.
           | 
           | My gut feeling though tells me that the best performance is
           | panels that use all the light or plants that get full access
           | to it.
        
         | r00fus wrote:
         | Plants can also get too much Sun just like they can be
         | overwatered.
         | 
         | That's where agrivoltaics and irrigation can help.
        
         | steve_adams_86 wrote:
         | This would vary so much by species of plant, cultivars within
         | species, local climate, etc. I suspect in your case it wouldn't
         | make sense, but in some places it's a common practice to shade
         | crops with raised sheets of cloth for example. In those cases,
         | assuming the shading is done fairly consistently (no need to
         | put panels up and down frequently), using panels could be a
         | great idea.
         | 
         | Where I live I need all the sun I can get as well. I have to
         | start tomatoes in mid February and get them into the soil in
         | June, and make sure they're either in my greenhouse where it's
         | warm or in the most exposed spots in my garden. If I shaded
         | anything my yields would be garbage.
        
         | KaiserPro wrote:
         | They do love sun, but they might not like intense heat.
         | 
         | Take those blueberries, Mine hate being in certain parts of the
         | patio because whilst they get full sun, they also get longer
         | and more extreme levels of heat. I almost lost them the year
         | before last.
         | 
         | (this is with a decent irrigation system too)
        
       | lpapez wrote:
       | Agrivoltaics seems like a cool idea but one of the things I
       | rarely ever see mentioned is how chemicals from the panels
       | interact with the crops. Steel can rust and if rust gets washed
       | away into the earth and then the plants... well that cant be
       | beneficial right? And I bet steel is the least toxic element of
       | the panels.
        
         | hosh wrote:
         | There are plants that can do soil remediation on soil with
         | heavy metals, though you can't eat them and you still have to
         | find a way to process or sequester the heavy metal. Cilantro
         | (coriander) is an example.
        
         | kibwen wrote:
         | Iron is often used as a fertilizer, so rusted support beams
         | aren't a problem, either for the plants or for humans. And all
         | the interesting parts of a solar panel are under glass, they
         | aren't being washed away by rain.
        
         | sigstoat wrote:
         | the solar facilities i'm familiar with use aluminum beams for
         | the structure. it is more than strong enough, lighter so it is
         | easier to install/ship to site, and requires no special
         | treatment to survive the environment for more than the life of
         | the installation.
         | 
         | the panels themselves do not contain steel, either.
         | 
         | > And I bet steel is the least toxic element of the panels.
         | 
         | perhaps, but nothing on the panels comes off. they're solid
         | objects largely impervious to all forms of precipitation. more
         | of your house washes away in a storm than comes off a panel.
        
         | hannob wrote:
         | Rust is just iron oxide, which in small quantities is a
         | relatively benign substance. And probably there's more rust
         | coming from old farming equipment than from the (likely high
         | quality, because they are built for expensive solar panels)
         | steel structures here.
         | 
         | The solar cells themselve are mostly made out of silicon, which
         | also isn't a dangerous substance.
         | 
         | I don't think this is an issue.
        
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       (page generated 2023-05-13 23:00 UTC)